Chris, many things were different 30 years ago. In retrospect, we all had it made. Construction was performed differently, with piles left on site for days if not weeks. Most sites were fenced but usually only locked to protect valuable equipment left there. These days things are proceeding at a much faster pace with pilings driven BEFORE earth removal and existing soil compacted when sufficient to carry the projected loads. The sites are seriously fenced and patrolled, so digging is often not an option. Thankfully, residential demo is still the same as it was. Mow down the building, clear the lot and go to the next one. This leaves a wide open chance to maybe excavate a privy or two or three.
We have had one site open for over 4 years because the developer shot his wad too quickly and lost the construction loans. We have dug over 40 pits from that entire one city block. There are undoubtedly more, but finding them will take time. Most of the ground has 18" of heavily compacted gravel that was under the blacktop and lots of rubble from demolition of homes 60 years ago.
Any site that even LOOKS like it has potential cannot be left untested. The way I see it if we don't slam it someone else darned sure will. Fences be damned, man the probes and shovels!
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